Designers Revital Cohen and Tuur Van Balen use both real and fictional biotechnology to explore the connection between the natural and the man-made, and invite questions about the impact of biotechnology. One of their projects, Life Support, imagines a world in which dogs and sheep take the role of life-saving medical devices. Their photos compel the viewer to ask: If the technology were available, would you want a greyhound respirator?

Cohen and Van Balen dreamed up Life Support in 2008 as an extreme extrapolation of the idea of assistance animals life guide dogs and therapeutic cats. They selected two animals—greyhounds and sheep—that are already bred for commercial use for their photo series. The "Respiratory Dog" is imagined as a retired racing hound that receives special training and a harness that uses the movements of the dog's chest to pump a mechanical ventilator connected to a tracheotomy tube in its human companion's neck.

The project description argues that it's a win-win. Instead of being euthanized or placed in a shelter (The Humane Society notes that greyhounds are often retired at 3.5-4 years old but can live to be 13), the dogs receive the affection and security of a constant human companion, while the human gets a furry respirator.

The imaginary "Dialysis Lamb" deals with a more invasive process as it cleans a patient's blood with its own kidneys. The idea is to create a transgenic lamb using the patient's own DNA who then lives with the patient. During the day, the lamb roams around outside, drinking and grazing, and then at night it is hooked up to the patient. While both lamb and human sleep, the lamb cleans with human's blood with its own kidneys.

Even if technologically feasible, both of these ideas come with plenty of logistical problems. But they do encourage us to consider: What line, if any, is there between a dog who fetches medication and other items for a disabled person and must be constantly vigilant for any difficulties her companion suffers, and a dog hooked up to a respirator harness? What is the line between using a sheep for its milk and wool and using its kidneys on a nightly basis?

What do you think? If these concepts were practical, would you have reservations about using them?